Wheel brake



F515t 14; 1928'.l 1,559,545

A. Y. DODGE WHEEL BRAKE- i Filed Deo. 2, 1924 2 Sheetssheet l IN1/Enron 40151. Y Dana/s' A. Y. Dogsa WHEEL BRKE Filed Dec. ,2. 1924 2 Sheets-Shen 2 7o/1. Y Doccia Patented Feb. 14, 1928.

UNITED y STATES l 1,559,545 PATENT OFFICE.v

ADIEL Y. DODGE, OF SOUTH BEND, INDIANA, ASSIGNOR TO BENDIX BRAKE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

WHEEL BRAKE.

application mea neaember a, 1924. serial No. 755,520.

This invention relates to brakes especially adapted for moving vehicles, particularly,

of the automotive type and has for its principal object the improvement in the construction and arrangement of brakes of the internal expanding type.

My invention has a further object to 1mprove the arrangement and operating characteristics of brakes ot the self energizing I0 type, wherein one shoe of the self energizing brake is acted on by another shoe constituting a part of the self energizing brake. It is a further object` of my inventlon to provide a construction and arrangement of a self energizing brake and an independent bra-ke such as shown in my co-pending application, Serial No. 723,836 filed July 2, 1924. It is a further object of my invention to obtain a braking mechanism having a plurality of brake shoes in which at least two;

of the shoes are substantially identical and interchangeable thereby reducing the number of different brake shoes and hence the cost of construction.

These and other objects will be apparent from astudy of the specification taken in connection with the annexed drawings wherein, l

Figure 1 is a side elevation showing three )0 brake shoes forming a complete braking mechanism, the` shoes' being shown in engagement with a rotating drum.

Figure 2 is a side elevation of Fig. 1 showing one form of brake operating means. $5 Figure Sis a fragmentary plan andsectional view of. the brake shoes showing the joint 2.

Figure 4 isa fragmentary plan andsectional view taken at the joint 3.

Figure 5 is a fragmentary plan and sectional view taken at the joint 1, While Figure 6 is a fragmentary sectional view on the lines 66 of Fig. 1.

Referring now to the detailswherein like '45 numbers refer to corresponding parts in their various views, 32 a brake drum. Within which is positioned-for engagement therewith, a braking mechanism comprising a self energizing brake made up of a primary shoe 4 and a secondary shoe 5 articulated or jointed at 1 as more' clearly shown in Fig. 5. An independent shoe 6 is anchored or pivoted by the pivot pin 2 to a stationary member such as acover plate 7 that also serves to u close the opening of the brake drum 32. The' 'necessary to go, into these details in this secondaryshoe 5 is also anchored' by a pi 3 to the cover plate 7. The brake sh0es 4 and 6 are constructed substantially identical so .that they are ,interchangeable in position thereby reducing the actual number of shoes to be manufactured to two, although the shoe 6 is used as an independent one, while the shoe 4 is a part of the self energizing brake comprising the shoes 4 and 5. It is to be understood that the shoes 4, 5, and 6 may be of any desired cross section, but in order to illustrate my invention I havev chosen to show shoes 4 and 6 as substantially T shaped beginning at the actuating ends and terminating in bifurcated portions toward the pivots 1 and 2, as shown in Fig. 3, While the shoe 5 is preferably T shaped throughout its length. As will be seen inFig. 3, the stem 8 oi the shoe 5 passes between the flanges of the1 channel shaped shoe 6 and is provided with a clearance hole 9, around the pivot stud 2 of the brake shoe 6. Similarly, the flanges of the brake shoe 6 has the clearance holes 10 for the pivot stud 3 of the shoe-5. The advantages of overlapping anchor points for the independent shoe 6 and the secondary shoe 5 have been clearly pointed out in my co-pending'application previously referred to so that it is not deemed application, except, to emphasize that this construction allows the heelsl of the shoes 5 and6 carrying the friction material 11, to

be brought. very closely together as indicated by the points-12 and 13; however, a further advantage is derived, from my present construction, by cutting away the web of the shoe 4 as indicated at 14, thereby allowing the flange 15, of the shoe 5, to extend a considerable distance beyond the articulated joint 1 bringing the points 16 and 17 of the shoes 4 and 5 very-l close together and since the'points 18` and 19 ad'a.-

cent the brake operating` means 20, which is shown in the form of a cam, are relatively 10( close together, the entire braking surface is made a maximum, it being only a'few degrees short of a full circumference.. The

brake shoe 4, has `a clearance hole 21, in which is positioned a holding device coinprismg a disc 22 and a spring 23 fastened to the plate 7 by a member ,24. The clearance hole 21 corresponds to the hole 10 as shown in brake shoe 6, the hole thus bein used in the case of brake shoe 4 for posl- 11n tioning an antirattling device and in the case of' brake shoe 6, as a clearance for anchor stud 3. The articulated joint 1 is adapted to'be acted onbdyt .an ad'ustable device whereby the joint 1 o' the brake shoe 5 may be adjusted outside the drum with respect to the drum. A spring 26 is utilized to return the shoe 5 to normal posi- 'tion after the brake operating means has ,A rangement for actuating the brakes, it is' to beundeistood that it maybe actuated by any other actuatingmeans, and it is to be further understood that the details for carrying my invention into practice may be modified to considerable extent Without de parting from the spirit of my invention orv the scope of the appended claims.

Having thus described my invention what Ivclaim is: f

'1. In brake mechanism for engaging a ro- A'tatable drum, a self energizing unit composedof articulated primary and secondary shoes, an independent 'shoe and means for.

causing all shoes to-engage said drum, said primary and independent shoes being similar and inter-changeable for the purposes described and different from the secondary shoe.

2. In brake tatable drum, a self energizing unit composed of articulated primary 'and Vsecondary shoes, an independent shoe and means for.

causing all shoes toengage said drum, one' of said shoes ot' the self energizing unit being inter-changeable with said independent shoe and the other not being interchangeable. L L

.3. Inbrake vmechanism Aforengagi'nga rotatable member, three brake 'shoes 'with i means for causing, said shoes to engage' the rotatable member, two of said shoes being y similar andl interchangeable and overlapping opposite ends ot the third shoe in com-- ybination Vith torque-taking means engaging the third shoe and one ofthe two' Vinterchangeable shoes. Y i

4. In brake mechanism for engaging a ro` 4tatablc member, three brake shoes with means for causing said'shoes tocngage the .rotatable members: two of said shoes being similarfand inter-changeableand disposed at opposite ends of the third shoe, one ot said v{Wto-Shoes being pivoted to the third shoe articulated shoes, and' means lmechanism for engaging a ro-` iuaess vwhile oneend of the other of said two shoes is pivoted to a stationary member.

5. In brake mechanism for engaging a rotatable member, three biakeshoes, tiro of which are similar and interchangeable means ffoi' acting on one end of each of said tivo shoes to move them into engagement with said rotatable member, said third shoe being anchored and being disposed between said two shoes and actuated by at least one of them. y

6. In brake mechanism for engaging a ro- :tatable member, three brake shoes, two ol which are similar and interchangeable, means for acting onv one end of each of said two shoes to move them into engagement with said rotatable member, said third shoe being disposed between said two shoes, and

vhaving one end pivoted by a relatively movable anchorage to one end of one ot said two shoes while the other iend of the third shoe and of the second of said two shoes,

have fixed pivots arranged `in ovler-1apping relationship'.

7; In brake mechanism for engaging a ro. tatable drum, a pair'of brake units, at least onev of which is composed of a lurality of or causing said units toI engage the drum, one unit being similar and interchangeable with a part only of the other unit.

8. In brake mechanism for engaging arotatable drum, ya self energizing unit composed. of articulated primary and secondary shoes, an independent shoe, ands` means for causing -all shoes to' engage said drum, said "secondary shoe having its braking surface extending be ond the articulated joint toward the hee of the primary shoe.

9. In brake mechanism for engaging a rotatable drum, a self energizing unit' com-v posed of articulated, primary and secbndary shoes, :in independent shoe and means for causing all shoes to engage said"A ruin, said secondary shoe and the iiidepe ident shoe havinfY overlappinganclior points and the secon ary shoe having .its toe extending some distance beyond the articulated joint and overlapping the pivot of the primary shoe.

-, 10. In brake. mechanism for engaging arotatable member, means for increasing'the effectiveness ot said mechanism comprising a plurality of shoes,rone of which has its 'I braking surface extending over the heelpivot portions of the two shoes adjacent its ends and being actuated by at least one of said two shoes. 4

11. In. brake mechanism for engaging a 'rotatable member, a self energizing unit, an

independent shoe, means for causingall ias shoes to engage said rotatable'vmembenonc portion ot the self energizingunit having a. part extending -over the pivot end of the other portion and another part also 'eXtending over the pivot portion of the independent shoe.

'12. In brake mechanism for engaging a rotatable drum. a self energizing 'unit composed ot articulated primary and secondary shoes, an independent shoe and means for causing all shoes to engage said drum, said primary shoe and inde-pendent shoe being channel shaped atleast at one end in cross section while the secondary shoe is T shape in cross section.

13. In brake mechanism for engaging a rotatable drum, a self energizing unit composed of articulated, primary and secondary shoes, an independent shoe and means -or causing all shoes to engage said drum said primary shoe and independent Shoe being channel shaped at least at one end in cross section and interchangeable, while said secondary shoe is T shaped in cross section.

14. In brake mechanism forqengaging a rotatable drum.y a self energizin yunit composed of articulated,` prirnary an. secondary shoes, an independent shoe and means for causing all shoes to engage said drum, 'said primary shoe and independent shoe being preferably T shaped from its actuating end and terminating in bifurcated portions to fwardtheir pivots While the secondary shoe is preferably T shaped in cross 'sectio throughout its lengbh. 15. A brake including an anchored central lshoe, and a pair of end shoes arranged at opposite ends of the central shoe, at least one of the end shoes being pivotcd to the central shoe between its ends.

16. A brake including a backing plate a central shoe, a pair of end shoes overlapping opposite ends of the central shoe, a pivot for connecting one of the end shoes to the central shoe and which has a head 'slidably engaging the backing plate, and a positioning stop carried by the backing plate and engaging said head 'of the pivot.

17. 'A brake includingr an anchored central shoe and a pair of forked end shoes straddling the end parts ot the central shoe, and applying means acting on the enc shoes and on the central shoe through one of the end shoes.

18. A brake including a central shoe and spring and bridging across the opening in said other shoe. y

19. A brake comprising a shoe with spaced `Web parts formed with opposite openings,

a part crossing the outer opening, and a stcadying spring passing through said openings and secured to said part.

20. A brake comprising a shoe with a web formed with an opening, a part crossing the opening, and a steadying sprino' passing through said opening and secured to said part.

21. A brake including a secondary shoe anchored at one end, and a primary shoe connected to the secondary shoe some distance from its free end, so that said free end overhangs the connection.

22.v A brake including a secondary shoe, a primary shoe connected to the secondary shoe some distance from `one end, so that said end overhangs the connection, and a spring arranged to hold the secondary shoe yieldingly in idleposition' in such a manner that the primary'shoe first swings about the connection and then overcomes the spring and applies the secondary shoe.

23. A brake including an anchored shoe, an end shoe, a pivot connecting the adjacent ends of said shoes, a'stop adjacent said pivot, and a spring urging the pivot against the stop when the brake is released and overcome in applying the brake by movement of said end shoe.

Q4. A brake including an anchored shoe, an end shoe, a ivot connecting the adjacent ends of said s oes, an adjustable eccentric adjacent said pivot, and a spring urging the pivot against the eccentric when the brake is released and overcome in applying the brake by movement of said end shoe.

25. A brake including a backing plate, a

pair of shoes arranged end to end, and a pivot connecting'said shoes and having one end slidably engaging the backing plato to serve as a steady rest for the shoes.

In testimony whereof I aix my signature.

' AD EL Y. DODGE. 

